JP7638189B2 - Manufacturing method for resin-bonded steel components - Google Patents

Description

The present invention relates to a manufacturing method for resin-bonded steel components and a heating device for resin-bonded steel components.

It is well known that resin-coated metal components such as clutch plates are manufactured by adhering paper that has been impregnated with a resin solution and cured to the surface of the metal component (see, for example, Patent Documents 1 to 3).

On the other hand, it is known to use a high-frequency heating device to dry a coating applied to a metal workpiece (see Patent Documents 4 and 5).

Patent Document 4 describes "an electrostatic coating method for coating the entire surface of a workpiece having an opening, comprising the steps of: a holding step of loosely inserting a holding jig having a pivot shaft into the opening of the workpiece and holding it; a position guiding step of keeping the end of the workpiece in the direction of the pivot shaft, which is loosely inserted in the holding step, in a non-contact state with other members; an electrostatic coating step of electrochemically depositing powder to be coated on the workpiece while rotating the loosely inserted holding jig about the pivot shaft of the holding jig; a provisional curing step of heating and melting the powder electrostatically coated on the workpiece by high-frequency induction; and a main curing step of heating and curing the insulating coating after the provisional curing step by irradiating it with far-infrared rays." (Claim 1).
It is also shown that the workpiece is transported by conveyor 9 in this order to electrostatic powder application section 11, temporary cure heating section (high frequency heating section) 12, and main cure heating section (far infrared heating section) 15 (see FIG. 3).

Patent document 5 describes, "[Claim 3] A coating drying method for drying a coating film applied to a metal substrate, the coating drying method comprising: a first drying step in which the coating applied to the substrate is heated by hot air, and the substrate is irradiated with near-infrared or mid-infrared rays in a wavelength range absorbed by the coating, thereby drying the coating; and a second drying step in which the substrate is heated by high-frequency induction, thereby drying the coating by heat transfer from the substrate."

In addition, when the workpiece is heated on a conveyor using a high-frequency (microwave) heating device or the like, it is also well known to use a belt made of heat-resistant fibers such as glass fiber or aramid fiber that do not easily absorb high-frequency (microwave) waves (see, for example, claim 1, paragraph [0031] of Patent Document 6, claim 8, paragraph [0034] of Patent Document 7, and paragraph [0017] of Patent Document 8).

Japanese Patent Application Publication No. 10-103396 Japanese Patent Application Publication No. 11-287274 Patent No. 6685069 Japanese Patent Application Publication No. 2-241563 Japanese Patent Application Publication No. 8-332434 JP 2011-99190 A JP 2006-59744 A JP 2000-306661 A

Patent documents 1 to 3 describe the production of resin-bonded metal components such as clutch plates by adhering paper that has been impregnated with a resin solution and cured to the surface of a metal component. However, they do not describe a method for continuously producing resin-bonded steel components by drying and curing the resin impregnated in such paper using a high-frequency heating device or the like.
On the other hand, Patent Documents 4 and 5 show the use of a high-frequency heating device to dry paint applied to a metal workpiece, but the objects to be coated are completely different. Patent Documents 6 to 8 show the use of a glass fiber or aramid fiber conveyor belt to heat a workpiece by high-frequency heating, but make no mention of using this to manufacture resin-bonded steel components.

The objective of the present invention is to provide a method for continuously and quickly drying and hardening a resin solution impregnated in paper adhered to the surface of a steel component.

In order to solve the above problems, the present invention employs the following means.
(1) A method for producing resin-bonded steel components by drying and hardening a resin solution impregnated in paper adhered to the surface of a steel component, in which the steel components are heated sequentially on a conveyor using a hot air heating device, a high-frequency heating device, and a far-infrared heating device, in that order.
(2) A manufacturing method for resin-bonded steel components as described in (1) above, in which a metal belt is used for the conveyor equipped with the hot air heating device, and a glass fiber or aramid fiber belt is used for the conveyor equipped with the high frequency heating device and the far infrared heating device.
(3) A method for manufacturing resin-bonded steel components according to (1) or (2), wherein the hot air heating device dries the surface of the steel components using hot air generated by a hot air generator and blown into a chamber.
(4) In the high-frequency heating device, one leg end of two inverted U-shaped conductors arranged in parallel is connected to the other leg end of the induction heating coil, and the leg end of the induction heating coil is placed across the steel components on the conveyor to heat them. This is a method for manufacturing resin-bonded steel components described in any of (1) to (3).
(5) A heating device for resin-bonded steel components, comprising a conveying device that conveys steel components having paper impregnated with a resin solution adhered to their surfaces on a conveyor, and a plurality of heating devices arranged on the conveyor in the following order along the conveying direction of the steel components: a hot air heating device, a high-frequency heating device, and a far-infrared heating device.

In the present invention, the resin solution impregnated in the paper adhered to the surface of the steel component can be dried and hardened continuously and quickly.

FIG. 1 is a schematic diagram showing the process of producing resin-bonded steel components on a conveyor according to one embodiment of the present invention. FIG. 2 is an enlarged view showing an example of a driving mechanism of a conveyor on which high-frequency heating devices and far-infrared heating devices are installed.

An embodiment of the present invention (hereinafter, referred to as "this embodiment") will be described with reference to FIG.
The steel members, with the paper adhered to their surfaces impregnated with the resin solution, are heated on conveyors 4a, 4b using a hot air heater 1, a high frequency heater 2 and a far infrared heater 3, in that order.
As the steel member is transported on the conveyor 4a, the surface of the paper is heated by the hot air heating device 1, and the solvent of the resin solution on the surface of the paper is evaporated and dried. Then, as the steel member is transported on the conveyor 4b, the high-frequency heating device 2 heats the steel member, and the solvent of the resin solution inside the paper (i.e., from the adhesive side of the paper to the steel member in the depth direction to the surface side) is evaporated and dried. The high-frequency heating device 2 is efficient because it heats up and heats up at a high speed. Next, the paper is heated by the far-infrared heating device 3. This heating is intended to stabilize the temperature, which has been raised at a high speed by the high-frequency heating device 2, at a constant temperature.
By successively heating the sheets in this order, the resin solution impregnated in the paper is hardened, forming a resin-bonded steel component.

The steel members referred to here include ordinary steel (carbon steel) and special steel in general, and refer to, for example, carbon steel such as rolled steel for general construction, steel for low temperature use, steel plate material for nuclear reactors, etc., and are ferrous materials such as cold-rolled steel, hot-rolled steel, hot-rolled steel plate material for automobile construction, hot-rolled high-tensile steel plate material for automobile processing, etc. Furthermore, the ferrous materials referred to in the present invention are not limited to the above steel materials, and include, for example, all ferrous materials standardized by the Japanese Industrial Standards (JIS "SS400") and the like.
The paper adhered to the surface of the steel member can be produced by papermaking using, for example, the same fiber components, fillers, etc. as are used in the production of normal clutch plates.

The fiber components may be selected from organic fibers such as pulp, polyester fibers, polyamide fibers, polyvinyl chloride fibers, polypropylene fibers, acrylic fibers, phenolic fibers, nylon fibers, and cellulose fibers, and inorganic fibers such as glass fibers, rock wool, ceramic fibers, silica fibers, potassium titanate fibers, and carbon fibers. As the filler, calcium carbonate, magnesium carbonate, silica, barium sulfate, alumina, magnesium oxide, zirconia, diatomaceous earth, silicon carbide, boron carbide, silicon nitride, boron nitride, and the like may be used. As the conditioner, cashew dust, graphite, and the like may be used. In the papermaking process, a mixed material containing these fiber components, fillers, and conditioners is first dispersed in water, and paper is made using a cylinder type papermaking machine or a fourdrinier type papermaking machine, and the paper is dried to form paper.
The resin solution impregnated in the paper adhered to the surface of the steel member may be, for example, a raw material solution of a thermosetting resin such as a phenol resin, a melamine resin, a urea resin, an epoxy resin, a polyester resin, or a urethane resin.

In addition, the heating device for resin-bonded steel components according to the present invention comprises the above-mentioned steel component having paper impregnated with a resin solution adhered to its surface, a transport device for transporting the steel component on conveyors 4a, 4b, and a plurality of heating devices 1, 2, 3 arranged on the conveyors 4a, 4b in the transport direction (flow direction) of the steel component in the following order: a hot air heating device 1, a high-frequency heating device 2, and a far-infrared heating device 3.
Since the heating device for resin-bonded steel components of the present invention has the configuration described above, it can continuously and quickly dry and harden the resin solution impregnated in the paper adhered to the surface of the steel components.

(Hot air heating device: symbol 1)
Before being subjected to high-frequency heating, the surface of the steel member is heated by hot air to evaporate the solvent (organic solvent) in the resin solution on the surface of the paper.
Hot air is blown into the chamber of the hot air heating device 1 installed on the conveyor 4a from a hot air generator (not shown) to heat the paper to a temperature at which the solvent (organic solvent) in the resin solution on the surface of the paper evaporates. The heating temperature and heating time can be set appropriately depending on the components of the resin solution and solvent (organic solvent) used.

(High frequency heating device: code 2)
After the resin on the surface of the steel component is dried with the hot air heating device 1, the steel component is heated with the high frequency heating device 2 to evaporate and dry the solvent of the resin solution inside the paper (i.e., from the adhesive side of the paper to the steel component in the depth direction to the surface side), thereby making it possible to dry the resin more quickly all the way to the inside when heating with the high frequency heating device 2. The heating temperature and heating time when heating with the high frequency heating device 2 can be set appropriately depending on the components of the resin solution and solvent (organic solvent) used.

As described in Japanese Patent No. 4620486, the high-frequency heating device 2 used in this embodiment preferably includes a coil of an inverted U-shaped conductor formed by connecting one leg end of two inverted U-shaped conductors arranged in parallel to each other and connecting a power source to the other leg end. By heating the leg end of the inverted U-shaped conductor of this induction heating coil by straddling the steel member on the conveyor 4b, the steel member can be heated efficiently and rapidly to the inside (deep part).

(Far infrared heating device: code 3)
After being high-frequency heated, the steel members are heated by a far-infrared heating device 3. This heating is performed by irradiating the steel members, including the paper, with far-infrared rays.
The purpose of this heating is to stabilize the temperature, which has been rapidly increased by the high frequency heating device 2, at a constant temperature.
When heating with the far-infrared heating device 3, the heating temperature and heating time can be appropriately set depending on the components of the resin solution and solvent (organic solvent) used.
By successively heating the sheets in this order, the resin solution impregnated in the paper is hardened, forming a resin-bonded steel component.

(Conveyor)
The conveyors 4a and 4b used in this embodiment will be described with reference to FIG.
The conveyor 4a on which the warm air heating device 1 is installed has rollers 6a, 6b at both ends of the conveyor body 5a, and an endless belt 7a is stretched between these rollers 6a, 6b to form a conveying path for transporting steel components on the upper surface of the conveyor body 5a.
In addition, the conveyor 4a has a conveyor body 5a, which serves as the machine frame, configured as a roughly long band when viewed in a plane, with the upper side of this conveyor body 5a, i.e., the transport path, being the outgoing path of the endless belt 7a, and the lower side of the same conveyor body 5a being configured as the return path of the endless belt 7a.

The endless belt 7a used in the conveyor 4a on which the hot air heating device 1 is installed may be made of metal. As the metal, it is preferable to use a stainless steel mesh.
That is, since the endless belt 7a is made of stainless steel mesh, hot air can be blown from below as well as from above the conveyor 4a in the hot air heating device 1. Therefore, even if paper impregnated with the resin solution is attached to both sides of the steel member, the stainless steel mesh allows the hot air to pass through, so that the solvent of the resin solution on the surface side can be evaporated by the paper on both sides of the steel member.

The conveyor 4b, on which the high-frequency heating device 2 and the far-infrared heating device 3 are installed, has rollers 6c and 6d at both ends of the conveyor body 5b, and a first endless belt 7b is stretched between these rollers 6c and 6d to form a conveying path for conveying steel members on the upper surface of the conveyor body 5b.
In addition, the conveyor 4b has a conveyor body 5b, which serves as the machine frame, configured as a roughly long band when viewed from above, and the upper side of this conveyor body 5b, i.e., the transport path, is configured as the outgoing path of the first endless belt 7b, and the lower side of the conveyor body 6b is configured as the return path of the first endless belt 7b.

By synchronizing the conveying speed of the conveyor 4b with the conveying speed of the conveyor 4a, the steel components can be smoothly transported from the conveyor 4a equipped with the hot air heating device 1 to the conveyor 4b equipped with the high frequency heating device 2 and the far infrared heating device 3.
The conveying speed of the conveyors 4 a and 4 b can be appropriately set depending on the heating time in the hot air heating device 1 , the high frequency heating device 2 and the far infrared heating device 3 .

The conveyor body 5a constructed as described above is provided with legs 8a, 8b, and 8c at both sides near both ends thereof, and at the portions supporting the hot air heater 1. That is, the conveyor body 5a is supported at a predetermined height by six legs.
The conveyor body 5b constructed as described above is provided with legs 8d, 8e, 8f, and 8g at both side portions near both ends thereof, and at portions supporting the high frequency heating device 2 and the far infrared heating device 3. In other words, the conveyor body 5b is supported at a predetermined height by eight legs.

The first endless belt 7b used in the conveyor 4b on which the high frequency heating device 2 and the far infrared heating device 3 are installed is preferably made of glass fiber or aramid fiber.
Glass fiber and aramid fiber have a heat resistance of 260°C or higher, do not absorb high frequencies easily, and do not generate heat themselves due to high frequency energy, making them ideal materials for the conveyor belt used in high frequency heating device 2 for drying and hardening the steel components having the adhesive of paper impregnated with the above-mentioned resin solution.
Furthermore, because the glass fiber and aramid fiber have a smooth surface, they do not get caught on the first endless belt 7b as it runs, and the steel members on the first endless belt 7b can be transported smoothly. When the steel members are high-frequency heated in the high-frequency heating device 2 within a short period of time, for example 20 seconds, everything is determined by the passage time, so it is important to prevent the first endless belt 7b from getting caught.

The first endless belt 7b made of glass fiber or aramid fiber is preferably a mesh made of fabric woven with glass fiber or aramid fiber. Made of glass fiber or aramid fiber does not mean a belt made only of glass fiber or aramid fiber, but also includes glass fiber or aramid fiber whose surface is coated with fluororesin (e.g., polytetrafluoroethylene: PTFE) or the like. Also, instead of glass fiber alone, a mixture of glass fiber and PTFE or the like, or a mixture of aramid fiber and other fibers may be used. A glass mat (nonwoven fabric) may also be used instead of a fabric.

Next, a drive mechanism of a conveyor on which the hot air heating device 1, the high frequency heating device 2 and the far infrared heating device 3 according to one embodiment of the present invention are installed will be described.
The drive mechanism of the conveyor in which the hot air heating device 1 is installed is similar to the drive mechanism of a conventional conveyor.
When the drive roller is driven by a motor, the endless belt 7a is rotated counterclockwise by the frictional force generated between the endless belt 7a and the outer circumferential surface of the drive roller, and the steel members on the endless belt 7a are transported from right to left.

FIG. 2 shows an example of a drive mechanism for a conveyor on which the high-frequency heating device 2 and the far-infrared heating device 3 are installed.
In the example of Figure 2, a driving mechanism is provided on the underside of the conveyor body 5b, which is provided with a rotating roller 9 that comes into contact with the return side of the first endless belt 7b to drive and rotate the belt, and two driven rollers 11a, 11b are arranged to sandwich both sides of the rotating roller 9 around which the first endless belt 7b is wound, via a second endless belt 10, and a driving roller 12 is provided below the driven rollers 11a, 11b, which comes into contact with the second endless belt 10 to drive and rotate the second endless belt 10.
The rotary roller 9 is provided which comes into contact with the return side of the first endless belt 7b to drive and rotate the first endless belt 7b. The first endless belt 7b is wound around the outer periphery of the rotary roller 9, and a second endless belt 10 made of rubber is further wound on top of the first endless belt 7b. The second endless belt 10 is brought into surface contact with the first endless belt 7b, and the second endless belt 10 is driven to rotate, thereby driving the rotary roller 9 to rotate.

As described above, since glass fiber or aramid fiber has a smooth surface, the first endless belt 7b made of glass fiber or aramid fiber does not get caught on the parts it runs through, and the steel members on the first endless belt 7b can be transported smoothly. However, on the other hand, slippage may occur between the rotating roller 9 and the first endless belt 7b. Therefore, in this embodiment, it is preferable to adopt the means described below.

That is, when the second endless belt 10 is driven to rotate by the drive roller 12, the two driven rollers 11a, 11b also rotate in a manner following the rotation of the second endless belt 10. Since the two driven rollers 11a, 11b are disposed on both sides of the rotating roller 9 around which the first endless belt 7b is wound as shown in Fig. 2, the first endless belt 7b and the second endless belt 10 are in surface contact with each other. Therefore, tension is applied to the first endless belt 7b, and the degree of contact between the first endless belt 7b made of glass fiber or aramid fiber and the outer circumferential surface of the rotating roller 9 can be increased.
Here, as described above, the material of the second endless belt 10 is rubber. As the rubber, any ordinary rubber can be used appropriately.

2, the rotating roller 9 is different from a conventional drive roller driven by a motor. The drive mechanism for driving the rotating roller 9 will now be described.
When the drive roller 12 is rotated in the direction of the arrow (clockwise), the second endless belt 10 is rotated clockwise due to the frictional force generated between it and the drive roller 12, and the rotating roller 9, which has two driven rollers 11a, 11b arranged on both sides via the second endless belt 10, is rotated in the direction of the arrow (counterclockwise) due to the frictional force generated between it and the second endless belt 10.

The first endless belt 7b is rotated counterclockwise by the frictional force generated between it and the outer circumferential surface of the rotating roller 9, and the steel members on the first endless belt 7b are transported from right to left.
As described above, the degree of adhesion between the first endless belt 7b made of glass fiber or aramid fiber and the outer peripheral surface of the rotating roller 9 can be increased, so that the driving force from the rotating roller 9 can be appropriately transmitted to the first endless belt 7b, enabling the steel components to be transported stably.

Next, a drive mechanism for driving the drive roller 12 will be described.
The drive mechanism for driving the drive roller 12 in this embodiment is similar to the drive mechanism for a conventional drive roller.
Two bearings (not shown) with bearings are provided to support the drive roller 12, and the drive roller 12 is horizontally supported between them for free rotation. The drive roller 12 is supported for free rotation by inserting a support shaft 12b through the shaft core of a hollow drive roller body 12a and fitting both ends of the support shaft 12b into the bearings.
One end of the support shaft 12b of the drive roller 12 protrudes through the bearing portion, and a sprocket 12c is attached and fixed to the protruding portion.

Meanwhile, a drive motor 13 with a reducer is installed next to the sprocket 12c of the drive roller 12. A sprocket 13c is provided on the output shaft (not shown) of the reducer, and the sprocket 13c and the sprocket 12c of the drive roller 12 are connected by an endless chain 14. Therefore, when the drive motor 13 is driven to rotate, the driving force is transmitted to the drive roller 12 via the sprocket 13c, the chain 14, and the sprocket 12c, driving the drive roller 12 to rotate at a predetermined rotation speed.

It is preferable to arrange two driven rollers 15a and 15b in parallel above the rotating roller 9 with an appropriate interval between them. When the first endless belt 7b rotates as described above, the two driven rollers 15a and 15b also rotate in a manner following the rotation of the first endless belt 7b. The return side of the first endless belt 7b is wound around the inside of the two driven rollers 15a and 15b and wound around the outer periphery of the rotating roller 9, so that the first endless belt 7b comes into contact with the outer periphery of the rotating roller 9 with an appropriate pressing force. When adjusting the tension of the first endless belt 7b, the pressure applied to the outer periphery of the rotating roller 9 can be adjusted by narrowing or widening the gap between the two driven rollers 15a and 15b to increase or decrease the degree of retraction of the first endless belt 7b.

The method for manufacturing resin-bonded steel components of the present invention can quickly dry and harden the solvent in the resin solution impregnated in the paper bonded to the surface of the steel component, making it applicable to the manufacture of automobile parts such as clutch plates.

1: Hot air heating device 2: High frequency heating device 3: Far infrared heating device 4a, 4b: Conveyor 5a, 5b: Conveyor body 6a, 6b, 6c, 6d: Roller 7a: Endless belt 7b: First endless belt 8a, 8b, 8c, 8d, 8e, 8f, 8g: Leg 9: Rotating roller 10: Second endless belt 11a, 11b: Driven roller 12: Drive roller 12a: Drive roller body 12b: Support shaft 12c: Sprocket 13: Drive motor 13c: Sprocket 14: Endless chain 15a, 15b: Driven roller

Claims (3)

This is a method for producing resin-bonded steel components by drying and hardening a resin solution impregnated in paper adhered to the surface of a steel component, in which the steel components are heated sequentially on a conveyor using a hot air heating device, a high-frequency heating device, and a far-infrared heating device, in that order , and in the high-frequency heating device, two inverted U-shaped conductors arranged in parallel have one foot end connected to the other foot end to a power source, to form an induction heating coil, whose foot is placed across the steel components on the conveyor and heated . The method for manufacturing resin-bonded steel components according to claim 1, wherein the conveyor equipped with the hot air heating device uses a metal belt, and the conveyor equipped with the high-frequency heating device and the far-infrared heating device uses a glass fiber or aramid fiber belt. The method for manufacturing resin-bonded steel components according to claim 1 or 2, wherein the hot air heating device dries the surface of the steel components with hot air generated by a hot air generator and blown into a chamber.

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